1. Field of the Invention
The present invention relates to a low sulfur diesel fuel composition having anti-wear properties. More specifically, the present invention relates to a low sulfur diesel fuel composition containing an amount of aminoalkylmorpholine effective to reduce wear to engine parts making metal to metal contact.
2. Description of Related Information
In response to ecological concerns, fuel companies have been selling low sulfur fuel oils nationwide since 1991. Combustion of sulfur containing fuels produces sulfur oxides, SO.sub.x, which reduce air quality and also fall to the ground in the form of acid rain. By removing sulfur from diesel fuels, or by using diesel fuels which are naturally low in sulfur, fuel companies have contributed to the cleanup of the air and waterways.
The use of low sulfur diesel fuels has had the side effect of increasing wear inside diesel engines at points which are lubricated by the fuel oil, and, more particularly, at light duty contact points in fuel injectors and pumps. Sulfur containing molecules react with metal surfaces to provide more efficient wear protection during metal to metal contact under high pressure rolling point content. The increasing use of low sulfur content diesel fuels will cause increased wear problems in fuel injectors and other moving metal parts which come in contact with this type of fuel.
For the foregoing reasons, refiners have resorted to adding lubricity agents to low sulfur diesel fuels to reduce wear in injectors and pumps. A problem associated with commercial lubricity agents, however, is that some of these agents are acidic. For example, one commercially available lubricity agent contains dimerized linoleic acid. These acids can react with basic amines, which are typically used as detergent additives in diesel fuels, to form harmful precipitates in the fuel. It would be useful, therefore, to provide a basic lubricity additive which would avoid these undesirable side reactions.
Applicant has discovered a basic, organic fuel additive which increases the lubricity of low sulfur diesel fuels and reduces the wear of moving metal parts which come in contact with the fuel in a diesel engine. This basic, organic fuel additive will not react with the basic, amine detergent additives to form precipitates, and thus overcomes this problem faced by the prior attempts to increase lubricity of low sulfur diesel fuels.